Nofollow

The nofollow attribute is a value that can be added to the rel attribute of an HTML anchor tag to instruct search engines not to follow the link or pass PageRank (link equity) through it. Originally introduced by Google in 2005 to combat comment spam, nofollow has evolved into a broader tool for managing how link equity flows across the web.

Google now treats nofollow as a "hint" rather than a strict directive, meaning it may choose to crawl, index, or consider nofollow links for ranking purposes at its discretion. In 2019, Google introduced two additional link attributes: rel="sponsored" for paid or sponsored links, and rel="ugc" for user-generated content like forum posts and comments. These provide more granular ways to identify the nature of links.

From an SEO perspective, nofollow links are commonly used in several contexts: editorial links that you do not want to endorse, paid or sponsored content links (required by Google's guidelines), user-generated content where you cannot vouch for the linked sites, and login pages or internal pages that do not need link equity. While nofollow links may not directly pass ranking power, they can still drive referral traffic and contribute to brand awareness. A natural backlink profile typically contains a mix of followed and nofollowed links.